OPINION
Defendant-Appellant Todd Hollenbaeh, the Treasurer of Kentucky, appeals the district court’s order declaring unconstitutional an amendment to section 393.060 of the Kentucky Revised Statutes. The amendment shortens the period after which state law imposes a presumption of abandonment on traveler’s checks, thereby accelerating the date at which the issuer of an unclaimed traveler’s check must remit the outstanding funds to the state. The district court determined that the amendment violated the Fourteenth Amendment Due Process Clause because it lacked a rational basis. Accordingly, the district court granted declaratory and injunctive relief to Plaintiff-Appellee American Express Travel Related Services Co. (“American Express”). Because we hold that the amendment does not violate the Due Process Clause, we VACATE the district court’s decision and REMAND the case for consideration of American Express’s remaining constitutional claims.
FACTUAL AND PROCEDURAL BACKGROUND
American Express is in the business of issuing traveler’s checks, which are preprinted “checks” in fixed dollar amounts ranging from $20-100. Upon the sale of a traveler’s check, either by American Express directly or through a third-party vendor, American Express receives the funds tendered for the check and records *687 the serial number of the cheek, its amount, and the date and place of sale; thereafter, American Express will honor the check in its full amount upon presentation by a holder in due course. American Express sells traveler’s checks to its customers at face value, that is, free of any service charges or fees. It profits from this business by investing the funds it receives from the sale of traveler’s checks, which it retains until the checks are redeemed. Traveler’s checks have no expiration date, and although the majority of purchasers cash their traveler’s checks within one year, American Express relies on a small percentage of traveler’s checks remaining uncashed for several years. It can therefore invest some funds from outstanding traveler’s checks in long-term, high-yield investments, up until state property law imposes a presumption of abandonment on uncashed traveler’s checks. At that point, American Express must remit the outstanding funds to the state. Until recently, all fifty states followed the presumption that a traveler’s check was abandoned if still outstanding more than fifteen years after issuance, as recommended in the Uniform Unclaimed Property Act.
In 2006, the Kentucky General Assembly shortened the presumptive abandonment period for traveler’s checks to seven years as part of its budget legislation for fiscal years 2007 and 2008 (the “2006 amendment”).
1
American Express claims that the legislation will render its traveler’s check business in Kentucky unprofitable, as the shorter presumptive abandonment period curtails its ability to place the funds from uncashed traveler’s checks in long-term investments. Consequently, American Express challenged the 2006 amendment in Kentucky state court under both the Kentucky Constitution and the Federal Constitution. The Franklin Circuit Court invalidated the enactment for failure to comply with the procedure for amending legislation required by Section 51 of the Kentucky Constitution, but it did not consider American Express’s other claims of unconstitutionality. An appeal of this decision was dismissed on procedural grounds by the Kentucky Court of Appeals,
Lassiter v. Am. Express Travel Related Seros. Co.,
Nos.2007-CA-000908, 2007-CA-000973,
In 2008, the Kentucky General Assembly again passed legislation amending section 393.060 to reflect a seven-year presumptive abandonment period for traveler’s checks (the “2008 amendment”). The enactment was incorporated into the budget legislation for fiscal years 2009 and 2010, as well as a separate bill designed to cure the procedural defects identified by the Franklin Circuit Court with respect to the 2006 amendment. In response, American Express filed suit in the United States District Court for the Eastern District of Kentucky against the Commonwealth of Kentucky, the Ken
*688
tucky Department of Treasury, and Todd Hollenbach, in his official capacity as Treasurer of Kentucky. American Express requested declaratory and injunctive relief, asserting that the 2008 amendment violates the Due Process Clause of the Fourteenth Amendment, the Contracts Clause of Article I, Section 10, and the Takings Clause of the Fifth and Fourteenth Amendments, as well as provisions of the Kentucky Constitution. The district court dismissed American Express’s state-law claims based on abstention principles and dismissed as defendants the Commonwealth and the Department of Treasury based on sovereign immunity.
Am. Express Travel Related Servs. v. Kentucky,
Both American Express and the Treasurer moved for summary judgment on American Express’s federal constitutional claims, and the district court granted summary judgment to American Express. The district court concluded that, because the 2008 amendment was intended as a revenue-raising measure, it did not satisfy rational basis review and it therefore violated substantive due process principles.
Am. Express Travel Related Servs. Co. v. Hollenbach,
STANDARD OF REVIEW
“This Court reviews de novo a district court’s grant of summary judgment.”
LensCrafters, Inc. v. Robinson,
ANALYSIS
I. Substantive Due Process Claim
In analyzing American Express’s substantive due process claim, the district court used “a two-part analysis” involving the determination of whether American Express’s interest in the unclaimed funds from issued traveler’s checks constitutes “a protected liberty or property interest under the Fourteenth Amendment.”
Hollenbach,
“ ‘[Legislation that does not proscribe fundamental liberties ... violates the Due Process Clause’ where it imposes burdens without any ‘rational basis’ for doing so.”
Sheffield v. City of Fort Thomas, Ky.,
The Treasurer argues on appeal that the district court misapplied the rational basis test under which we evaluate American Express’s substantive due process claim. Specifically, the Treasurer asserts that the district court improperly looked to the General Assembly’s actual legislative purpose in passing the 2008 amendment when, in fact, “the courts must affirm the constitutionality of a legislative enactment if it is rationally related to any conceivable legitimate state purpose, regardless of what the ‘real’ intent of the legislature may have been in passing the legislation.” The Treasurer contends that, upon consideration of his proffered purpose for the 2008 amendment, the legislation passes consti *690 tutional muster. We agree that the district court erroneously applied a stricter form of rational basis review. We further hold that the district court erred in granting summary judgment to American Express on its substantive due process challenge.
A. The Scope of Rational Basis Review
In his motion for summary judgment, the Treasurer argued that the 2008 amendment survives rational basis scrutiny because: (1) Kentucky has a legitimate interest in taking possession of abandoned property; and (2) this purpose is rationally related to the seven-year presumptive abandonment period for traveler’s checks. The district court found that this interest cannot be considered a legislative purpose behind the 2008 amendment. Instead, the district court determined that, in light of the 2008 amendment’s legislative history and the Franklin Circuit Court’s factual findings relating to the 2006 amendment, “it is clear that the state’s objective [in passing the 2008 amendment] was to raise revenue rather than to reunite citizens with lost property.”
Hollenbach,
The district court erred in deciding that it could not consider Kentucky’s interest in assuming possession of unclaimed property as a purpose supporting the 2008 amendment. As the Supreme Court often has reiterated, the party challenging a legislative enactment subject to rational basis review must “ ‘negative every conceivable basis which might support it.’ ”
See, e.g., Lehnhausen v. Lake Shore Auto Parts Co.,
In concluding that the 2008 amendment should not be evaluated under this “very permissive rational basis test,” the district court relied on the following statement in
United States Trust Co. of New York v. New Jersey,
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tionality of a wide range of legislation, contravening Supreme Court precedent applying the standard rational basis test to such measures.
See, e.g., Fitzgerald v. Racing Ass’n of Cent. Iowa,
The district court also read
Anderson National Bank v. Luckett,
American Express offers a third argument in support of the district court’s heightened rational basis scrutiny, citing past cases from the Supreme Court and this Court rejecting the government’s proffered legitimate objectives when the challenged legislation appeared to be based on an illegitimate purpose.
See City of Cleburne, Tex. v. Cleburne Living Ctr.,
B. Application to the 2008 Amendment
We are required to entertain the Treasurer’s rational speculation that the 2008 amendment was intended to facilitate Kentucky’s interest in assuming possession of abandoned property, even though, as the district court found, the legislative history does not reflect whether this goal was actually considered by the General Assembly. 4 Because this objective constitutes a legitimate state purpose and the seven-year presumptive abandonment period is rationally related to that purpose, the 2008 amendment does not violate substantive due process guarantees.
It cannot be doubted that Kentucky has a legitimate interest in enacting legislation that allows the state to take custody of property that is presumed abandoned.
See Anderson Nat’l Bank,
Nevertheless, the General Assembly rationally could have concluded that traveler’s checks are no less likely to be abandoned after being unredeemed for seven years, as opposed to fifteen years.
Cf. Cunnius v. Reading Sch. Disk,
Because American Express has not carried its “heavy burden of ‘negativing] every conceivable basis which might support [the 2008 amendment],’ ”
Hadix v. Johnson,
II. Remaining Constitutional Claims
American Express asserts that we may affirm the district court’s judgment invalidating the 2008 amendment on alternative grounds, namely that it violates the Takings Clause, it violates the Contracts Clause, or its retroactive application to traveler’s checks already sold violates the Due Process Clause. The district court denied the Treasurer’s motion to dismiss these claims on the pleadings,
American Express v. Kentucky,
CONCLUSION
For the foregoing reasons, we VACATE the judgment of the district court invalidating the 2008 amendment to section 393.060 of the Kentucky Revised Statutes on substantive due process grounds. We REMAND the case to the district court for consideration of American Express’s *695 remaining constitutional challenges in proceedings consistent with this opinion.
Notes
. After the passage of the Kentucky legislation, New Jersey also departed from the presumption that traveler's checks are abandoned after fifteen years. See 2010 N.J. Laws 25 (amending the New Jersey Unclaimed Property Law to reflect a three-year presumptive abandonment period for traveler’s checks). American Express has also challenged that legislation in the United States District Court for the District of New Jersey. The district court's denial of a preliminary injunction against the legislation, Am. Express Travel Related Servs. Co. v. Sidamon-Eristoff, 755 F.Supp.2d 556 (D.N.J.2010), is currently on appeal to the United States Court of Appeals for the Third Circuit.
.
See Romer,
. American Express also claims that the Treasurer’s proffered purpose violates Section 51 of the Kentucky Constitution and is therefore illegitimate. The district court correctly dismissed this contention, along with the rest of American Express’s state law claims, because federal courts lack the power to enjoin a violation of state law.
See Pennhurst State Sch. & Hosp. v. Halderman,
. American Express argues, for the first time on appeal, that "the doctrine of judicial estoppel bars the Treasurer from taking the inconsistent position here that the purpose of the Legislation is to reunite owners and their property.” According to American Express, the Treasurer’s claims are "clearly inconsistent with his earlier, successful argument [to the Franklin Circuit Court] that the Legislation is a revenue raiser.” However, as discussed in the previous section, rational basis review allows the government to proffer "rational speculation” as to a statute’s purpose, regardless of actual or admitted legislative objectives.
Craigmiles,
